I'm six feet tall. So, the top of the quarter panels on the Chevy 'hit' me about shoulder height. Maybe a little lower, but not much.
@Brandon Van de Graaff for me to reach half of the spark plugs I have to, literally, climb on top of the engine. No big deal there. BUT...
If you are facing the truck, the plug on the right side, far back, is damn near impossible to reach without buying a specific extension (my best guess.)
(I ran into a similar problem working on the brakes a few years ago when the CM nut I had to remove was one size larger than your 'normal kit' contained. So, a trip to ACE for that. I want to say it was 32mm. My set (70 pieces, I think) didn't go that high and a friend of mine's set went to 31 (as I recall.) I digress...)
I ended up with a HD ratchet, 12" extension connected to another, then the socket to remove the plug. So, four different 'tools' to remove one plug.
Geez, replacing the pump for the windshield wiper fluid had me cussing like that: Toyota. I had to re-wire the damn thing with little to no room. (IF I had a lift...)
DIY guys on cars, etc., ... he's right, they hate us.